Perivascular Leak Repair System

ABSTRACT

The perivascular leak repair system, and method of using the same, of the present invention provides a sealant reservoir  102  with a repair catheter  104  operably attached; a flow control device  106  disposed between the sealant reservoir  102  and the repair catheter  104,  and the flow control device  106  responsive to a flow control signal  108;  a heart phase detector  114  generating a diastole phase signal  112;  an injection switch  122  generating a injection signal  120;  and a flow controller  110  responsive to the diastole phase signal  112  and the injection signal  120,  and generating the flow control signal  108.  A method of sealing a perivascular leak comprises identifying the perivascular leak  140;  inserting a repair catheter to the perivascular leak  142;  injecting sealant at the perivascular leak  144;  and removing the repair catheter  146.  The sealant can be injected when the heart is in diastole to sweep the sealant into the perivascular leak.

TECHNICAL FIELD

The technical field of this disclosure is medical devices, particularly,perivascular leak repair systems and method of using the same.

BACKGROUND OF THE INVENTION

Heart valves, such as the aortic valve, are sometimes damaged by diseaseor by aging, which can cause problems with the proper function of thevalve. Heart valve problems generally take one of two forms: stenosis,in which a valve does not open completely or the opening is too small,resulting in restricted blood flow; or insufficiency, in which bloodleaks backward across the valve that should be closed. Valve replacementmay be required in severe cases to restore cardiac function.

Valve replacement can be performed through open-heart surgery, openchest surgery, or percutaneously. The native valve is removed andreplaced with a prosthetic valve, or a prosthetic valve is placed overthe native valve. The open chest and percutaneous procedures avoidopening the heart and cardiopulmonary bypass. Regardless of theprocedure used, perivascular leakage can occur around the prostheticvalve and cannot be detected until the heart is closed and beating.

FIG. 1 shows a prosthetic aortic valve implanted in the aorta.Perivascular leakage, i.e., back flow from the ascending aorta 20 to theleft ventricle 22 during diastole, will occur if the prosthetic aorticvalve 24 is not sealed in the aorta, creating a perivascular leak 26.Some perivascular leakage may heal shut over time, but the healing isuncertain and the leakage reduces valve function until the healing iscomplete. Currently, repair of perivascular leakage requires anopen-heart surgery to repair the leak with additional sutures. Repairmay also require replacement of the prosthetic valve if the prostheticvalve size is incorrect. Open-heart surgery involves risk, expense, andan extended recovery time. Open-heart surgery also requirescardiopulmonary bypass with risk of thrombosis, stroke, and myocardialinfarction.

It would be desirable to have a perivascular leak repair system thatwould overcome the above disadvantages.

SUMMARY OF THE INVENTION

One aspect of the present invention provides a perivascular leak repairsystem that provides immediate perivascular leak repair.

Another aspect of the present invention provides a perivascular leakrepair system that avoids open-heart surgery for perivascular leakrepair.

Another aspect of the present invention provides a perivascular leakrepair system that uses leakage flow to carry sealant into theperivascular leak.

Another aspect of the present invention provides a perivascular leakrepair system that avoids injecting unnecessary sealant in thecirculatory system.

The foregoing and other features and advantages of the invention willbecome further apparent from the following detailed description of thepresently preferred embodiments, read in conjunction with theaccompanying drawings. The detailed description and drawings are merelyillustrative of the invention, rather than limiting the scope of theinvention being defined by the appended claims and equivalents thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a prosthetic aortic valve implanted in the aorta.

FIG. 2 shows a perivascular leak repair system inserted percutaneouslyand made in accordance with the present invention.

FIG. 3 shows a perivascular leak repair system inserted through theaortic wall and made in accordance with the present invention.

FIGS. 4A & 4B show detailed and general block diagrams, respectively, ofa perivascular leak repair system made in accordance with the presentinvention.

FIG. 5 shows a flow chart for a method of using a perivascular leakrepair system made in accordance with the present invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENT

FIG. 2 shows a perivascular leak repair system inserted percutaneously.A repair catheter is advanced percutaneously to the perivascular leakand sealant injected at the perivascular leak. The sealant injection canbe coordinated with the heartbeat to sweep the sealant into theperivascular leak.

In the example shown, the repair catheter 40 can be inserted inguinallyinto the femoral artery and advanced until the distal tip 42 is near theperivascular leak 44 at the prosthetic aortic valve 48. The location ofthe perivascular leak 44 can be determined using echocardiography beforeinserting the repair catheter 40. The location of the distal tip 42relative to the perivascular leak 44 can be determined by an imaging ornavigation system. In one embodiment, the distal tip 42 can have aradiopaque marker 46 and fluoroscopy can be used to locate the distaltip 42. In another embodiment, a non-fluoroscopic navigation system,such as the Localisa® intracardiac navigation system from Medtronic,Inc., of Minneapolis, Minn., can be used to locate the distal tip 42.The Localisa® intracardiac navigation system uses three skin electrodepairs, positioned in x, y, z directions around the heart to trackcatheters. In yet another embodiment, fluoroscopy can be used inconjunction with a non-fluoroscopic navigation system to locate thedistal tip 42.

The repair catheter 40 can be any catheter that can locate a distal tip42 near the perivascular leak 44 and includes a lumen 50 to inject asealant. In one embodiment, the repair catheter 40 can be steerable,such as the MyoCath™ catheter from Bioheart, Inc., MyoStar catheter fromJohnson & Johnson, Inc., or the Stiletto catheter from BostonScientific, Inc. In another embodiment, the distal tip 42 can haveretractable needle or corkscrew elements to connect the distal tip 42with the cardiac tissue at the perivascular leak 44.

When the distal tip 42 is at or near the perivascular leak 44, a sealantcan be injected through a lumen 50 in the repair catheter 40 to seal theperivascular leak 44. The sealant can be any non-toxic sealant that canflow into or cover over the perivascular leak 44. The sealant can flowinto and adhere to the walls of the perivascular leak 44. The sealantcan degrade with time with tissue ingrowth maintaining the seal.

The sealant can use the body's own clotting and repair mechanisms tostop the perivascular leak. In one embodiment, the sealant can be fibringlue. Fibrin glues are typically made by contacting a solution orsuspension of the blood protein fibrinogen with an enzyme or otherreagent which can crosslink it. Typically, the enzyme thrombin is used,which cleaves the fibrinogen molecule, forming fibrin monomer which thenspontaneously polymerizes. This is a natural reaction involved in theformation of blood clots. Fibrinogen can be obtained from the patient orfrom pooled homologous human blood. The blood protein fibrinogen andenzyme thrombin can be injected through separate lumens in the repaircatheter so that the two components meet and mix at the perivascularleak. In another embodiment, the sealant can be collagen paste. Collagenpaste is typically collagenous material ground to a fine powder andmixed with water or aqueous saline solution until injectable. Thecollagen paste is thrombogenic, so that it will form clots and recruitfibrin in the perivascular leak.

Other sealants which can be used to seal the perivascular leak include,but are not limited to, activated platelet gel, hydrogels, N-butylcyanoacrylate, isobutyl-2 cyanoacrylate, alkyl cyanoacrylate, siliconerubber, Ethibloc amino acid gel, autologous material such as fat dura,EVAL ethylene vinyl alcohol copolymer, EMBOLYX ethylene vinyl alcoholcopolymer, poly-vinyl alcohol, alginates such as polysachrides,posphoryl choline-hydrogel, activated microparticles, combinationsthereof, and the like.

The repair catheter 40 can also have a pressure sensor 52 for sensingpressure in the ascending aorta 58. The pressure sensor 52 can transmita pressure signal to the heart phase detector, which can use thepressure signal to determine when the heart is in diastole. Sealantinjected during diastole will follow the backflow from the ascendingaorta 58 into the perivascular leak 44 to provide a superior sealwithout releasing substantial sealant into the circulatory system. Inone embodiment, the repair catheter 40 can include a pressure lumenexiting near the distal tip 42 to transmit the pressure in the ascendingaorta 58 to a pressure sensor mounted external to the patient or mountedproximally the distal tip 42 within the repair catheter 40 itself. Inyet another embodiment, the pressure sensor can be omitted and anelectrocardiogram (ECG) used to determine diastole. In yet anotherembodiment, the repair catheter 40 can include a Doppler echo probe fordetecting flow and determining diastole. The Doppler echo probe can alsobe used for imaging the perivascular leak, the prosthetic valve, and thesurrounding structure. The Doppler echo probe can also be used to detectemboli.

A filter 54 can be disposed on the repair catheter 40 across theascending aorta 58 before the brachiocephalic artery to catch and retainsealant or other emboli discharged during the perivascular leak repairprocedure. In another embodiment, a separate filtering device, such asthe Scion Cardio-Vascular SCI-PRO® guide wire based retrieval devicefrom Scion Cardio-Vascular, Inc., of Miami, Fla., can be inserted inparallel with the repair catheter 40 to remove embolic material duringthe perivascular leak repair.

FIG. 3, in which like elements share like reference numbers with FIG. 2,shows a perivascular leak repair system inserted through the aorticwall. Accessing the perivascular leak 44 through the aortic wall avoidsopening the heart itself and is possible when the chest is open. Thisapproach is particularly advantageous if a perivascular leak isdiscovered after open chest valve replacement surgery, but before thechest is closed. A repair catheter 40 is placed through the aortic walland sealant injected at the perivascular leak 44 from the lumen 50. Thesealant injection can be coordinated with the heartbeat to sweep thesealant into the perivascular leak.

FIGS. 4A & 4B show detailed and general block diagrams, respectively, ofa perivascular leak repair system. The control system coordinatessealant injection with the heartbeat to sweep the sealant into theperivascular leak.

FIG. 4A shows one embodiment of perivascular leak repair system. Theperivascular leak repair system 80 comprises a syringe 82 providingsealant to a repair catheter 84 through a flow control valve 86. Theflow control valve 86 is responsive to a flow control signal 88 from aflow controller 90 to stop or allow sealant flow from the syringe 82 tothe repair catheter 84. The flow controller 90 is responsive to adiastole phase signal 92 from the heart phase detector 94.

In use, the repair catheter 84 is advanced so that the distal tip isnear the perivascular leak. The syringe 82 and flow control valve 86remain outside the patient. The heart phase detector 94 monitorsheartbeat using pressure at the distal tip of the repair catheter 84 oran electrocardiogram (ECG). When the heart phase detector 94 detects theheart is in diastole, the heart phase detector 94 sends a diastole phasesignal 92 to the flow controller 90 indicating the same. The flowcontroller 90, in turn, sends a flow control signal 88 to the flowcontrol valve 86 directing the flow control valve 86 to permit flow. Ifthe surgeon is applying pressure to the syringe 82, sealant will flowthrough the flow control valve 86 and the repair catheter 84 to enterthe perivascular leak with the backflow through the perivascular leak.During systole, the flow control valve 86 is closed and no flow ispermitted through the repair catheter 84. Applying sealant duringdiastole, and not during systole, gets the sealant into the perivascularleak where required and avoids excess sealant being carried into thecirculatory system.

FIG. 4B shows another embodiment of perivascular leak repair system. Theperivascular leak repair system 100 comprises a sealant reservoir 102providing sealant to a repair catheter 104 through a flow control device106. The flow control device 106 is responsive to a flow control signal108 from a flow controller 110 to stop or allow sealant flow from thesealant reservoir 102 to the repair catheter 104. The flow controller110 is responsive to a diastole phase signal 112 from the heart phasedetector 114 and an injection signal 120 from the injection switch 122.The flow controller 110 can also be responsive to an injection amountsignal 116 from the injection amount selector 118.

The sealant reservoir 102 and flow control device 106 are selected toprovide sealant flow to the repair catheter 104. In one embodiment, thesealant reservoir 102 can be pressurized and the flow control device 106can be a valve. In another embodiment, the flow control device 106 canbe a pump. Separate sealant reservoirs and flow paths can be providedfor multi-part sealants that activate on mixing.

In use, the repair catheter 104 is advanced so that the distal tip isnear the perivascular leak. The sealant reservoir 102 and flow controldevice 106 remain outside the patient. The heart phase detector 114monitors heartbeat using pressure at the distal tip of the repaircatheter 104, an electrocardiogram (ECG), or a Doppler echo probe. Whenheart phase detector 114 detects the heart is in diastole, the heartphase detector 114 sends a diastole phase signal 112 to the flowcontroller 110 indicating the same. When the injection switch 122 isactivated by the surgeon providing an injection signal 120 to the flowcontroller 110, and the heart phase detector 94 detects the heart is indiastole providing a diastole phase signal 92, the flow controller 110sends a flow control signal 108 to the flow control device 106 directingthe flow control device 106 to permit flow. Sealant will flow throughthe flow control device 106 and the repair catheter 104 to enter theperivascular leak with the backflow through the perivascular leak eachtime the heart is in diastole until the surgeon releases the injectionswitch 122. Flow is stopped each time the heart is in systole, eventhough the surgeon maintains the injection switch 122 in the injectposition. The flow controller 110 can also be responsive to an injectionamount signal 116 from the injection amount selector 118 to limit to apredetermined amount the amount of sealant injected each time the heartis in diastole or to limit the amount of sealant injected each time thesurgeon pushes the injection switch 122.

Emboli detection can be provided to detect emboli that might occur fromor during the procedure. In one embodiment, the emboli detector can be aDoppler echo probe disposed on the repair catheter 104. In anotherembodiment, the emboli detector can be external, such as transcranialDoppler (TCD) ultrasound or the like.

FIG. 5 shows a flow chart for a method of using a perivascular leakrepair system. A perivascular leak is identified at 140. A repaircatheter is inserted to the perivascular leak 142 and sealant injectedat the leak 144. The repair catheter is removed at 146. Typically, thesealant can be fibrin glue, collagen paste, activated platelet gel, orthe like.

Identifying the perivascular leak 140 can comprise identifying theperivascular leak by echocardiography. While the repair catheter isinserted to the perivascular leak 142, the repair catheter can belocated by an imaging or navigation system, such as fluoroscopy or aLocalisa® non-fluoroscopic intracardiac navigation system fromMedtronic, Inc. Injecting sealant at the perivascular leak 144 cancomprise monitoring heart phase for diastole and injecting sealant atthe perivascular leak during the diastole, and further comprise notinjecting sealant during systole. The method can further comprisechecking whether the perivascular leak is sealed and injecting sealantat the perivascular leak if the perivascular leak is not sealed. Thiscan be repeated until the perivascular leak is sealed.

It is important to note that FIGS. 1-5 illustrate specific applicationsand embodiments of the present invention, and is not intended to limitthe scope of the present disclosure or claims to that which is presentedtherein. For example, the perivascular leak repair system of the presentinvention can be used for other heart valves in addition to the aorticvalve. Different arterial and venous approaches to the perivascular leakcan also be used. Upon reading the specification and reviewing thedrawings hereof, it will become immediately obvious to those skilled inthe art that myriad other embodiments of the present invention arepossible, and that such embodiments are contemplated and fall within thescope of the presently claimed invention.

While the embodiments of the invention disclosed herein are presentlyconsidered to be preferred, various changes and modifications can bemade without departing from the spirit and scope of the invention. Thescope of the invention is indicated in the appended claims, and allchanges that come within the meaning and range of equivalents areintended to be embraced therein.

1-10. (canceled)
 11. A method of sealing a perivascular leak comprising:identifying the perivascular leak 140; inserting a repair catheter tothe perivascular leak 142; injecting sealant at the perivascular leak144; and removing the repair catheter
 146. 12. The method of claim 11wherein the sealant is selected from the group consisting of fibringlue, collagen paste, activated platelet gel, hydrogels, N-butylcyanoacrylate, isobutyl-2 cyanoacrylate, alkyl cyanoacrylate, siliconerubber, Ethibloc amino acid gel, autologous material, fat dura, EVALethylene vinyl alcohol copolymer, EMBOLYX ethylene vinyl alcoholcopolymer, poly-vinyl alcohol, alginates, polysachrides, posphorylcholine-hydrogel, activated microparticles, and combinations thereof.13. The method of claim 11 wherein identifying the perivascular leak 140comprises identifying the perivascular leak by echocardiography.
 14. Themethod of claim 11 further comprising locating the repair catheter witha system selected from the group of an imaging system, a navigationsystem, a fluoroscopy system, and a non-fluoroscopic intracardiacnavigation system.
 15. The method of claim 11 wherein injecting sealantat the perivascular leak 144 comprises monitoring heart phase fordiastole and injecting sealant at the perivascular leak during thediastole.
 16. The method of claim 15 further comprising injectingsealant at the perivascular leak only during the diastole.
 17. Themethod of claim 11 wherein injecting sealant at the perivascular leak144 comprises injecting sealant at the perivascular leak in apredetermined amount.
 18. The method of claim 11 further comprising:checking whether the perivascular leak is sealed; and injecting sealantat the perivascular leak if the perivascular leak is not sealed.
 19. Themethod of claim 11 wherein inserting a repair catheter to theperivascular leak 142 comprises inserting a repair catheter into theascending aorta.
 20. The method of claim 19 wherein inserting a repaircatheter into the ascending aorta comprises inserting a repair catheterinto the ascending aorta by a route selected from the group consistingof through the groin percutaneously and through the aortic wall.
 21. Themethod of claim 11 wherein the repair catheter has a distal tip andfurther comprising inserting a filter proximal the distal tip.
 22. Asystem for sealing a perivascular leak comprising: means for identifyingthe perivascular leak 140; means for inserting a repair catheter to theperivascular leak 142; means for injecting sealant at the perivascularleak 144; and means for removing the repair catheter
 146. 23. The systemof claim 22 wherein the sealant is selected from the group consisting offibrin glue, collagen paste, activated platelet gel, hydrogels, N-butylcyanoacrylate, isobutyl-2 cyanoacrylate, alkyl cyanoacrylate, siliconerubber, Ethibloc amino acid gel, autologous material, fat dura, EVALethylene vinyl alcohol copolymer, EMBOLYX ethylene vinyl alcoholcopolymer, poly-vinyl alcohol, alginates, polysachrides, posphorylcholine-hydrogel, activated microparticles, and combinations thereof.24. The system of claim 22 wherein the means for identifying theperivascular leak 140 is echocardiography.
 25. The system of claim 22further comprising means for locating the repair catheter.
 26. Thesystem of claim 22 wherein means for injecting sealant at theperivascular leak 144 comprises means for monitoring heart phase fordiastole and means for injecting sealant at the perivascular leak duringthe diastole.
 27. The system of claim 26 further comprising means forinjecting sealant at the perivascular leak only during the diastole. 28.The system of claim 22 wherein the means for injecting sealant at theperivascular leak 144 comprises means for injecting sealant at theperivascular leak in a predetermined amount.
 29. The system of claim 22further comprising: means for checking whether the perivascular leak issealed; and means for injecting sealant at the perivascular leak if theperivascular leak is not sealed.
 30. A perivascular leak repair systemcomprising: a syringe 82; a repair catheter 84, the repair catheter 84being operably attached to the syringe 82; a flow control valve 86, theflow control valve 86 being disposed between the syringe 82 and therepair catheter 84, and being responsive to a flow control signal 88; aheart phase detector 94, the heart phase detector 94 generating adiastole phase signal 92; and a flow controller 90, the flow controller90 being responsive to the diastole phase signal 92 and generating theflow control signal
 88. 31. The system of claim 30 wherein the heartphase detector 94 monitors heartbeat using input from a device selectedfrom the group consisting of a pressure sensor 52 disposed on the repaircatheter 40, a Doppler echo probe disposed on the repair catheter 40,and an electrocardiogram.